VDR and melanoma: studied the VDR Taq1 and Fok1 polymorphisms and found that the combined variant tt/ff genotype (Taq1 and Fok1) was associated with tumors thicker than 3.5 mm (OR = 31.5, p = 0.001) [16], while homozygosity for the wild-type allele of the Fok1 (FF) correlated with a reduced melanoma risk.